ABUNDANCE DETERMINATION OF AN INTRACLUSTER MEDIUM BY RESONANT SCATTERING EFFECT

ABSTRACT

It is important to reconsider the radiative process in an intracluster medium, since the optical depth of Fe-K emission lines at the central core region is around unity by resonant scattering effect. It causes uncertainty of abundance determination by a factor of two at most. Two clusters 3C129(z=0.0218) and A3667(z=0.0556) are selected for this purpose under criteria of high intensity, temperature of 5-7keV, isothermality and large angular size fit well to GIS field of view. Additionally 3C129 located in the direction of galactic plane is useful to observe the small scale distribution of absorbing gas in our galaxy by shadowing effect.